1. Field of the Invention
The present invention relates in general to a detecting apparatus using a digital computer, and more in particularly to a detecting apparatus for rendering a control specification to coincide with a standard specification.
2. Description of the Prior Art
In a detecting apparatus using a digital computer, the resistance value of a heat-sensitive resistor or a variable resistor or the value of the electromotive force of a piezoelectric element used as an input element is provided usually as a converted value of a predetermined range of voltages, so that the A/D converted digital value of the voltage is used to determine the input condition of the digital computer thereby to control an output element. The characteristic variations of the individual elements directly affecting the voltage conversion, however, present themselves as variations of the control specification of a final product, and therefore, the variations of the control specifications are required to be held within a predetermined tolerance by preshipment adjustment.
In a widely-used method, the characteristics of the input elements, namely, the relation between the physical factors and the value of a generated voltage is adjusted within the range of the standard characteristics by use of a variable correction resistor or a pre-amplifier with the gain thereof controllable.
The greatest disadvantage of this method is that a considerable number of adjustment steps is involved.